SMN: Proteins and Enzymes

SMN (Gemin 1) is the central component of a large oligomeric complex (SMN complex), including Gemins 2-7, that is necessary and sufficient for the in vivo assembly of Sm proteins onto the small nuclear (sn)RNAs that mediate pre-mRNA splicing. The SMN complex is found in the cytoplasm and nucleus. Within the nucleus, this protein localizes to subnuclear bodies called gems which are found near coiled bodies containing high concentrations of small ribonucleoproteins (snRNPs). Spinal muscular atrophy, a motor neuron disorder, results from reduced levels or a mutation in the Gemin 1 protein.